Neural inhibition in the rat lower esophageal sphincter: role of beta 3-adrenoceptor activation.
1. Electrical field stimulation (EFS) of the rat lower esophageal sphincter produced tetrodotoxin-sensitive relaxant responses. 2. The relaxant responses were not significantly affected by propranolol but were attenuated by 6-hydroxydopamine and cyanopindolol, indicating beta 3-adrenoceptor activation. 3. The relaxant responses were significantly reduced in tissues previously exposed to BRL 37344, a beta 3-adrenoceptor agonist. 4. It was concluded that EFS-induced relaxation was adrenergic in origin and was mediated by beta 3-adrenoceptors.
Oriowo
M A
MA
Department of Pharmacology and Toxicology, Faculty of Medicine, Kuwait University, Safat, Kuwait.
D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid / Q000494:pharmacology; D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002065:Buspirone / Q000494:pharmacology; D002217:Carbachol / Q000494:pharmacology; D004558:Electric Stimulation; D004594:Electrophysiology; D004943:Esophagogastric Junction / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure*; D004983:Ethanolamines / Q000494:pharmacology; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects / Q000502:physiology; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D016627:Oxidopamine / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000502:physiology*; D022702:Receptors, Adrenergic, beta-3; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology; D014662:Vasoconstrictor Agents / Q000494:pharmacology
D000318:Adrenergic beta-Agonists; D000319:Adrenergic beta-Antagonists; D004983:Ethanolamines; D011943:Receptors, Adrenergic, beta; D022702:Receptors, Adrenergic, beta-3; D017366:Serotonin Receptor Agonists; D014662:Vasoconstrictor Agents; D013779:Tetrodotoxin; C057368:BRL 37344; D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; D001285:Atropine; D016627:Oxidopamine; D002217:Carbachol; D011433:Propranolol; D019001:Nitric Oxide Synthase; D002065:Buspirone